Omega Owners Forum - Off with its head (s)!!!

Marks DTM Calib

Administrator

Offline

Ex Member

Posts: 25671
Northern Hemisphere
Gender: male

Drives: Astra J, Mum Bus, Dexta Tractor, 108 DMU wip

Re: Off with its head (s)!!!
Reply #60 - 07. Mar 2009 at 09:49

PaulW wrote on 06. Mar 2009 at 23:15:

I'm confused...

Facelift has different nuts for holding the manifold in place, yet same studs???

Part numbers differ on the nuts...

Yep, they are a 10mm head rather than 13mm.

Will try to establish why later but, it may well be to make it easier to get a deep socket on them with the larger manifold body

Back to top

IP Logged

Marks DTM Calib Administrator Offline Ex Member Posts: 25671 Northern Hemisphere Gender: Drives: Astra J, Mum Bus, Dexta Tractor, 108 DMU wip	Re: Off with its head (s)!!! Reply #61 - 07. Mar 2009 at 09:58 MikeDundee wrote on 07. Mar 2009 at 02:18: Kepp up the good work Mark .....just one query though, thought you were just gonna keep an eye on the tyre pressures .....why's the engine in bits Ow bugger, forget to do the tyres! Not a problem though, there on ebay so will have a new owner shortly!
Back to top	IP Logged

Taxi Driver

Omega Lord

Offline

OOF Holly Dog

Posts: 8413
Swindon
Gender: male

Drives: Fiat Scudo 90 Multijet (whatever that means!)

Re: Off with its head (s)!!!
Reply #62 - 07. Mar 2009 at 11:44

Marks DTM Calib wrote on 07. Mar 2009 at 09:58:

MikeDundee wrote on 07. Mar 2009 at 02:18:

Kepp up the good work Mark Thumbs Up!

.....just one query though, thought you were just gonna keep an eye on the tyre pressures Lips Sealed

.....why's the engine in bits Lips Sealed

Ow bugger, forget to do the tyres!

Not a problem though, there on ebay so will have a new owner shortly!

Yes, it would look a lot better with steel rims on it Thumbs Up!

I would suggest getting some wheel trims like these to top it off Thumbs Up!

http://cgi.ebay.co.uk/Pimp-your-ride-Spinning-spinner-BLING-Car-Wheel-Trims_W0QQ...

Back to top

Want 250mins talk/unlimited text/unlimited data?...for £10/month no contract?...then order a free sim and get £5 credit free...clicky on following link... http://giffgaff.com/orders/affiliate/taxi_driver

IP Logged

Martin Imber Over Active Poster Offline LPG Omega V6 - Keyfobs Rebuilt Posts: 20110 Worcester Gender: Drives: 2001 Omega 2.6CD LPG & 3.0 cams	Re: Off with its head (s)!!! Reply #63 - 07. Mar 2009 at 20:22 Can you carry out a plastiscene test and find out what minimum valve piston clearance is? It is a very usefull test
Back to top	The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect. IP Logged

Marks DTM Calib

Administrator

Offline

Ex Member

Posts: 25671
Northern Hemisphere
Gender: male

Drives: Astra J, Mum Bus, Dexta Tractor, 108 DMU wip

Re: Off with its head (s)!!!
Reply #64 - 07. Mar 2009 at 20:31

Martin Imber wrote on 07. Mar 2009 at 20:22:

Can you carry out a plastiscene test and find out what minimum valve piston clearance is?

It is a very usefull test

Not easily and anyway, pointless unless your going for custom ground cams plus we already know the max useable lift is around 10-11mm!

had a look at a few bits today, the pistona have a very slight dish but, they also do NOT come to the top of the bore like the 2.5 and 3.0!

So, we do at least know for definate how the compression has been lowered!

Back to top

IP Logged

Martin Imber

Over Active Poster

Offline

LPG Omega V6 - Keyfobs
Rebuilt

Posts: 20110
Worcester
Gender: male

Drives: 2001 Omega 2.6CD LPG & 3.0 cams

Re: Off with its head (s)!!!
Reply #65 - 07. Mar 2009 at 20:38

Marks DTM Calib wrote on 07. Mar 2009 at 20:31:

Martin Imber wrote on 07. Mar 2009 at 20:22:

Can you carry out a plastiscene test and find out what minimum valve piston clearance is?

It is a very usefull test

Not easily and anyway, pointless unless your going for custom ground cams plus we already know the max useable lift is around 10-11mm!

had a look at a few bits today, the pistona have a very slight dish but, they also do NOT come to the top of the bore like the 2.5 and 3.0!

So, we do at least know for definate how the compression has been lowered!

So unless there are some 2.5 style 2.6 pistons (there isn't) skimming is pratical - provided the inlet divider is trimmed as well.

Doing this on my Sunbeam worked out a 60 thou skim was possible, that was quite a bit higher than before.

Thinking of trying 20 thou if practical - if I get a spare set of heads to fettle before May - no hope of reburbishing and regrinding in two heads in one evening.

I am aiming for 10.8:1 as that will work fine, but I don't think I could skim that much off.

Back to top

The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect.

IP Logged

VXL V6

Omega Lord

Offline

Posts: 5306
Gender: male

Re: Off with its head (s)!!!
Reply #66 - 07. Mar 2009 at 20:43

Martin Imber wrote on 07. Mar 2009 at 20:38:

Marks DTM Calib wrote on 07. Mar 2009 at 20:31:

Martin Imber wrote on 07. Mar 2009 at 20:22:

Can you carry out a plastiscene test and find out what minimum valve piston clearance is?

It is a very usefull test

Not easily and anyway, pointless unless your going for custom ground cams plus we already know the max useable lift is around 10-11mm!

had a look at a few bits today, the pistona have a very slight dish but, they also do NOT come to the top of the bore like the 2.5 and 3.0!

So, we do at least know for definate how the compression has been lowered!

So unless there are some 2.5 style 2.6 pistons (there isn't) skimming is pratical - provided the inlet divider is trimmed as well.

Doing this on my Sunbeam worked out a 60 thou skim was possible, that was quite a bit higher than before.

Thinking of trying 20 thou if practical - if I get a spare set of heads to fettle before May - no hope of reburbishing and regrinding in two heads in one evening.

I am aiming for 10.8:1 as that will work fine, but I don't think I could skim that much off.

Not sure how you propose to do that? If you skim the heads to that degree then the inlets are going to sit lower and closer to the centre so the plastic divider will be useless as it won't meet the heads and neither will the bolt holes.

Back to top

Opelscanner
SP V6 Cam Lock
VX Trade Card

IP Logged

Martin Imber Over Active Poster Offline LPG Omega V6 - Keyfobs Rebuilt Posts: 20110 Worcester Gender: Drives: 2001 Omega 2.6CD LPG & 3.0 cams	Re: Off with its head (s)!!! Reply #67 - 07. Mar 2009 at 20:51 0.5mm off each one - just under 0.25mm off each side of the inlet divider. 54 deg/2 is near enough to 30 so 1 root3 2 triangle AFAIR so 0.5mm is 0.25mm then root 3 to a little under it All rough on paper!
Back to top	The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect. IP Logged

PaulW Omega Knight Offline Come on you fiend! Posts: 1998 53.25732, -2.52633 Gender: Drives: '51 Astra Eco4 & BMW R1200GSA	Re: Off with its head (s)!!! Reply #68 - 07. Mar 2009 at 20:59 Will .8 compression really make that much difference??
Back to top	Humbugs... IP Logged

VXL V6

Omega Lord

Offline

Posts: 5306
Gender: male

Re: Off with its head (s)!!!
Reply #69 - 07. Mar 2009 at 21:00

Martin Imber wrote on 07. Mar 2009 at 20:51:

0.5mm off each one - just under 0.25mm off each side of the inlet divider.

54 deg/2 is near enough to 30 so 1 root3 2 triangle AFAIR so 0.5mm is 0.25mm then root 3 to a little under it

All rough on paper!

Actually I do follow that! Roll Eyes

But thinking on, the inlets aren't at 54deg to each other as they aren't flush on the side of the heads.
I guess you'd also need to be careful re the coolant bridge.

James's oil cooler 'how-to' pictures shows what I mean:-

http://www.omegaowners.com/forum/YaBB.pl?num=1221081908

Back to top

« Last Edit: 07. Mar 2009 at 21:02 by VXL V6 »

Opelscanner
SP V6 Cam Lock
VX Trade Card

IP Logged

Martin Imber

Over Active Poster

Offline

LPG Omega V6 - Keyfobs
Rebuilt

Posts: 20110
Worcester
Gender: male

Drives: 2001 Omega 2.6CD LPG & 3.0 cams

Re: Off with its head (s)!!!
Reply #70 - 07. Mar 2009 at 21:03

VXL V6 wrote on 07. Mar 2009 at 21:00:

Martin Imber wrote on 07. Mar 2009 at 20:51:

0.5mm off each one - just under 0.25mm off each side of the inlet divider.

54 deg/2 is near enough to 30 so 1 root3 2 triangle AFAIR so 0.5mm is 0.25mm then root 3 to a little under it

All rough on paper!

Actually I do follow that! Roll Eyes

But thinking on, the inlets aren't at 54deg to each other as they aren't flush on the side of the heads. I guess you'd also need to be carfeful re the coolant bridge.

James's oil cooler 'how-to' pictures shows what I mean:-

http://www.omegaowners.com/forum/YaBB.pl?num=1221081908

Hmmm the angle makes it more difficult to work out - the sides would be 0.5mm approx nearer so need about 0.25mm slack in the bolt holes.

All to be thought about anyway

Back to top

The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect.

IP Logged

Martin Imber Over Active Poster Offline LPG Omega V6 - Keyfobs Rebuilt Posts: 20110 Worcester Gender: Drives: 2001 Omega 2.6CD LPG & 3.0 cams	Re: Off with its head (s)!!! Reply #71 - 07. Mar 2009 at 21:06 PaulW wrote on 07. Mar 2009 at 20:59: Will .8 compression really make that much difference?? Yes - Look at this thread earlier - they tuned the DBW engines to make up for power loss. I reckon 2 or 3 bhp minimum would be found but also better mpg
Back to top	The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect. IP Logged

JamesV6CDX Ex Member Gender: Drives: 2002 (02) 3.2 Retail MV6 in Star Silver with Leather	Re: Off with its head (s)!!! Reply #72 - 07. Mar 2009 at 21:09 Martin Imber wrote on 07. Mar 2009 at 21:06: PaulW wrote on 07. Mar 2009 at 20:59: Will .8 compression really make that much difference?? Yes - Look at this thread earlier - they tuned the DBW engines to make up for power loss. I reckon 2 or 3 bhp minimum would be found but also better mpg Is it worth it, for a barge?
Back to top	www.omegamechanic.co.uk - Mobile Mechanics Service in support of Help for Heroes. IP Logged

Martin Imber

Over Active Poster

Offline

LPG Omega V6 - Keyfobs
Rebuilt

Posts: 20110
Worcester
Gender: male

Drives: 2001 Omega 2.6CD LPG & 3.0 cams

Re: Off with its head (s)!!!
Reply #73 - 07. Mar 2009 at 21:11

JamesV6CDX wrote on 07. Mar 2009 at 21:09:

Martin Imber wrote on 07. Mar 2009 at 21:06:

PaulW wrote on 07. Mar 2009 at 20:59:

Will .8 compression really make that much difference??

Yes - Look at this thread earlier - they tuned the DBW engines to make up for power loss.

I reckon 2 or 3 bhp minimum would be found but also better mpg

Is it worth it, for a barge?

Since I use a high octane fuel I think it could save a bit of fuel

Back to top

The other tuned 2.6. DIY LPG, towbar, upgrade ICE & Wing Spoiler, Air shocks, Eibach Pro Springs, Poly WB bushes, WIM setup, HID conversion, 3.0 cams, ported ect.

IP Logged

Marks DTM Calib

Administrator

Offline

Ex Member

Posts: 25671
Northern Hemisphere
Gender: male

Drives: Astra J, Mum Bus, Dexta Tractor, 108 DMU wip

Re: Off with its head (s)!!!
Reply #74 - 08. Mar 2009 at 08:30

JamesV6CDX wrote on 07. Mar 2009 at 21:09:

Martin Imber wrote on 07. Mar 2009 at 21:06:

PaulW wrote on 07. Mar 2009 at 20:59:

Will .8 compression really make that much difference??

Yes - Look at this thread earlier - they tuned the DBW engines to make up for power loss.

I reckon 2 or 3 bhp minimum would be found but also better mpg

Is it worth it, for a barge?

Given the additional cost is small and only involves time (your won)......then why wouldn't it be Thumbs Up!

Back to top

IP Logged

This is the old site. Please use the new site.

This is the old site. Please use the new site.

www.omegaowners.com/forum/index.php.

This is the old site. Please use the new site.

	Welcome, Guest. Please Login